Accessible Bus Stop

Our project has several bus stops within the 1/4 mile radius, and what I would consider to be the most direct route along the street to the stops is also within 1/4 mile walking distance. However, for a portion of the walking path (about 1/10 mile) there is no sidewalk or other pedestrian friendly route from the building to the bus stop. I can't find anything that says that the route has to be predefined with a sidewalk or path just that it must be within the 1/4 mile. Can anyone tell me if I'm over thinking it, or whether they will require some type of predefined path in order for these stops to be compliant?